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A027866 Numbers n such that n^2 + (n+1)^2 + (n+2)^2 + (n+3)^2 + (n+4)^2 + (n+5)^2 is prime. 6
2, 3, 4, 9, 12, 13, 18, 19, 21, 23, 24, 32, 34, 38, 48, 51, 52, 56, 62, 63, 81, 82, 87, 96, 97, 102, 104, 109, 119, 128, 142, 146, 152, 158, 159, 164, 166, 167, 199, 212, 214, 217, 219, 221, 223, 224, 229, 233, 236, 238, 249, 251, 258, 269, 273, 277, 284, 291, 296 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers n such that 55 + 30n + 6n^2 is prime. - Zak Seidov, May 20 2014

LINKS

Zak Seidov, Table of n, a(n) for n = 1..10000

P. De Geest, World!Of Numbers

MATHEMATICA

Select[Range[6!], PrimeQ[#^2 + (# + 1)^2 + (# + 2)^2 + (# + 3)^2 + (# + 4)^2 + (# + 5)^2] &] (* Vladimir Joseph Stephan Orlovsky, Dec 20 2009 *)

PROG

(MAGMA) [n: n in [0..400] | IsPrime(55+30*n+6*n^2)]; // Vincenzo Librandi, Nov 18 2010

(PARI) is(n)=isprime(n^2+(n+1)^2+(n+2)^2+(n+3)^2+(n+4)^2+(n+5)^2) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

Sequence in context: A125774 A062410 A145772 * A283596 A281992 A100902

Adjacent sequences:  A027863 A027864 A027865 * A027867 A027868 A027869

KEYWORD

nonn

AUTHOR

Patrick De Geest

STATUS

approved

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Last modified November 23 00:33 EST 2017. Contains 295107 sequences.